Dual action drill pipe mud wiper

ABSTRACT

A resilient drill pipe mud wiper having a dual wiping action that is capable of being mounted on the drill pipe below a split bushing of a rotary table that drives a Kelly. As the drill pipe is moved upwardly from a bore hole containing drilling mud, the mud wiper by a dual wiping action removes mud adhering to the drill pipe therefrom and allows the scraped drilling mud to drain downwardly into the bore hole by gravity. The mud wiper is of such structure that a bit of greater transverse cross section than that of the drill pipe to which it is secured, may pass through the mud wiper without damage to the latter.

United States Patent 1 Tate 1 1 DUAL ACTION DRILL PIPE MUD WIPER [76]Inventor: Robert B. Tate, 945 Locust Ave.,

No. 16, Long Beach, Calif. 90813 [22] Filed: July 25, 1973 21 Appl. No.:382,514

[52] US. Cl. 175/84, 15/210 B [51] Int. Cl E211) 33/08 [58] Field ofSearch 175/84; 166/81; 15/210 B [56] References Cited UNITED STATESPATENTS 2,392,146 1/1946 Hall 166/81 UX 2,568,247 9/1951 Medearis 15/210B 2,611,146 9/1952 Buckley 15/210 B 2,655,679 10/1953 Grant 15/210 B2,809,012 10/1957 Stevens 175/84 X 2,966,690 1/1961 Taylor 15/210 B3,061,862 11/1962 Minor 15/210 B 3,466,693 9/1969 Grant 175/84 X July9,1974

FOREIGN PATENTS OR APPLICATIONS 668,987 3/1952 Great Britain 15/210 BPrimary ExaminerDavid H. Brown [57] ABSTRACT A resilient drill pipe mudwiper having a dual wiping action that is capable of being mounted onthe drill pipe below a split bushing of a rotary table that drives aKelly. As the drill pipe is moved upwardly from a bore hole containingdrilling mud, the mud wiper by a dual wiping action removes mud adheringto the drill pipe therefrom and allows the scraped drilling mud to draindownwardly into the bore hole by gravity. The mud wiper is of suchstructure that a bit of greater transverse cross section than that ofthe drill pipe to which it is secured, may pass through the mud wiperwithout damage to the latter.

10 Claims, 6 Drawing Figures PATENTEDJUL 91974 3.822.753

Figure 2 Figure 3 Figure 5 DUAL ACTION DRILL PIPE MUD WIPER 7 BACKGROUNDOF THE INVENTION 1. Field of the Invention Dual action drill pipe mudwiper.

2. Description of the Prior Art In the past, the removal of drilling mudadhering to a drill pipe as the latter is raised upwardly in a bore holehas been a troublesome problem.

The primary purpose in devising the present invention is to supply a mudwiper in which the components defining same are locked into fixedrelationship with one another, and as a result a resilient mud wiper isprovided that is of unitary structure and one that has a dual wipingaction on drill pipe as the latter is moved upwardly through theinvention.

A further object in devising the present invention is to supply a mudwiper for drill pipe that is of such structure that a bit of greatertransverse cross section than that of the drill pipe may beinadvertently drawn through the mud wiper without doing damage thereto.

SUMMARY OF THE INVENTION A dual action mud wiper adapted for beingdisposed below the split bushing of a rotary table on a drilling rig,and when so positioned capable of having a drill string moved upwardlytherethrough to remove mud adhering to the drill string.

The device includes a stiffener ring of substantially greater internaldiameter than the external diameter of the drill pipe. The stiffenerring is enveloped in the ring shaped peripheral portion of a flatgenerally circular body, which body is formed from a resilient material,preferably rubber. The body inwardly from the peripheral portiondevelops into upper and lower sheets, which sheets are separated by aspace of substantial depth. The upper and lower sheets have coaxiallyaligned upper and lower circular openings formed therein, which openingsare of slightly less diameter than the external diameter of the drillpipe.

The lower sheet has two lower ports formed therein on opposite sides ofthe lower opening, and the lower opening and two lower ports beingconnected by two lower slits. The upper sheet has two upper ports formedtherein on opposite sides of the upper opening, and these upper portsbeing connected to the upper opening by two upper slits. The upper andlower slits are preferably normally disposed to one another.

The lower opening, lower slits and two lower ports cooperate to definetwo lower flaps in the mud wiper which deform upwardly to wipe mud fromthe drill pipe as the drill pipe is moved upwardly through the device.The upper sheet also has two upper flaps formed therein due to thecooperation of the upper openings, upper slits and upper ports, withthese upper flaps also tending to move upwardly and wipe mud from thedrill pipe as the drill pipe is moved upwardly through the device.

The lower pair of flaps and the upper flaps are separated by a space ofsufficient depth that the flaps do not contact one another when deformedupwardly. Mud that is carried on the drill string upwardly past thelower pair of flaps is removed from the drill string by the second pairof flaps and flows into the space previously mentioned, with the mudsubsequently draining from this space by flowing downwardly through thelower pair of ports into the bore hole. The upper pair of ports at alltimes maintains the space in a vented condition, to permit mud carriedtherein to flow freely therefrom by gravity through the lower port intothe bore hole. The stiffener ring maintains the circular generally flatbody in this configuration during the time that the drill string isbeing moved upwardly therethrough. Both the stiffener ring and theresilient body may be formed from rubber, but with the stiffener ringhaving a substantially greater Shore hardness than the Shore hardness ofthe body.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a combined side elevationaland vertical cross sectional view of a portion of a drilling rig and themud wiper in engagement with a drill string;

FIG. 2 is a top plan view of the mud wiper when disposed in the positionshown in FIG. 1;

FIG. 3 is a bottom plan view of the mud wiper when disposed in theposition shown in FIG. 1;

FIG. 4 is a transverse cross sectional view of the mud wiper;

FIG. 5 is a side elevational view of the mud wiper; and

FIG. 6 is a transverse cross sectional view of the mud wiper, with adrill string being moved upwardly therethrough, and illustrating themanner in which the mud wiper exerts a dual wiping action on the drillstring to remove mud therefrom.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. I a portion of adrilling rig is shown that includes a split bushing 1 that is drivinglysupported in a rotary table 2 that is mounted on the floor 3 of aderrick (not shown). The mud wiper 4, which is the present invention, isshown in engagement with a drill pipe 5 that is being moved upwardlythrough the bushing l by conventional means (not shown).

The mud wiper 4 includes a stiffener ring 6 that has an internaldiameter that is substantially greater than the external diameter of thedrill pipe 5. The stiffener ring 6 is embedded in the peripheral portionof a circular, generally flat resilient body 7 that is preferably formedfrom rubber. The resilient ring 6 is preferably formed from rubberhaving a Shore hardness of between to 95, while the Shore hardness ofthe body 7 is preferably within a range of 55 to 65. The body 7 inwardlyfrom the peripheral portion thereof develops into a circular secondportion, which portion includes an upper and a lower sheet 8 and 9respectively. The upper and lower sheets 8 and 9 respectively havecentrally disposed coaxially aligned openings 9 and 10 formed thereinthat are of slightly smaller diameter than the external diameter thanthe drill pipe 5 that they are to engage.

The upper sheet 8 has two upper ports 11 formed therein that aresituated on opposite sides of the upper opening 9 with these upper ports11 being connected by slits 12 to the upper opening 9. The upper opening9, upper port 11, and upper slits 12, cooperate to define a pair ofupper flaps 13 in the upper sheet 8, which flaps deform upwardly whenthe drill pipe is moved upwardly relative to the mud wiper 4 as shown inFIG. 6. The upper and lower sheets 8 and 9 respectively are separated bya space 14 as best seen in FIG. 4.

The lower sheets 9 as can best be seen in FIG. 3 has two lower ports 14formed therein on opposite sides of the lower opening 10, with the lowerports being connected to the lower opening 10 by two slits 15. The loweropening 10, the lower pair of ports 14 and the lower pair of slits orslots 15 cooperate to define two flaps 16 that may deform upwardly towipe mud from the drill pipe 5 as the latter is moved upwardly throughthe mud wiper 4 when the latter is disposed as shown in FIG. 1. It willbe noted in FIGS. 2 and 3 that the upper flap 13 are angularly disposedrelative to the lower flaps I6 with this angulation preferably being 90.

In FIG. 6 it will be seen that as the drill pipe 5 is moved upwardlythrough the mud wiper 4, the lower flaps l6 deform upwardly to wipe mudfrom the drill pipe, and any mud passing these flaps entering the space14. Mud entering the space 14 may flow downwardly therefrom by gravitythrough the two lower ports 14. The upper ports 11 at all times maintainthe space 14 in a vented condition, so that no negative pressure isformed therein that tends to restrain the free flow of mud therefromthrough the lower ports 14. Any mud entering the space 14 is scrapedtherefrom by the upwardly deformed uppwer flap l3, and this scraped mudrunning downwardly into the space 14 to drain therefrom through thelower port 14. Mud draining from the mud wiper 4 by gravity, fallsdownwardly into the bore hole (not shown) from which the drill string 5is being raised upwardly. The stiffener ring 6 prevents the body 7 fromdeforming out of its flat configuration as shown in FIG. 4 when drillpipe is moved upwardly through the mud wiper 4 as illustrated in FIG. 1.

The use and operation of the invention has previously been explained indetail and need not be repeated.

I claim:

1. In combination with an oil well drilling rig having a rotary tablethat includes a split bushing through which drill pipe that supports abit may be moved upwardly from a bore hole containing drilling mud, adevice for subjecting said drill pipe to a dual wiping action to removesaid mud therefrom as said drill pipe is moved upwardly relative to saidrotary table when said device is situated below said bushing, saiddevice including:

a. a stiffener ring of substantially greater diameter than the externaldiameter of said drill pipe; and

b. a circular, generally flat, resilient body that includes aring-shaped peripheral portion which envelopes said stiffener ring, withsaid body inwardly from said peripheral portion developing into upperand lower sheets that define a space of substantial depth therebetween,said upper and lower sheets having coaxially aligned upper and lowercircular openings formed therein of slightly lesser diameter than theexternal diameter of said drill pipe, and with those portions of saidupper and lower sheets defining said upper and lower openings being inpressure wiping contact with the exterior surface of said drill pipe,said lower sheets having two oppositely disposed ports formed therein onopposite sides of said lower opening, which lower sheet has twooppositely disposed lower slits formed therein that extend between saidlower opening and said two lower ports and said two lower slitscooperatively defining two oppositely disposed lower flaps in said lowersheet that deform upwardly to wipe mud from said drill pipe as thelatter is moved upwardly relative to said device, and with any of saidmud on said drill pipe that passes said lower flaps entering said spaceand draining therefrom by gravity through said lower ports into saidwell bore.

2. The device as defined in claim 1 wherein said stiffener ring isformed from rubber having a first shore hardness and said body is formedfrom rubber having a second shore hardness substantially less than saidfirst shore hardness.

3. The device as defined in claim 2 wherein there is a differential ofat least 20 between the shore hardness of said body and said stiffenerring.

4. The device as defined in claim 2 wherein said first shore hardnesslies in a range of between and 95.

5. The device as defined in claim 4 wherein said second shore hardnessis substantially 60.

6. The device as defined in claim 1 in which said upper sheet has twoupper ports defined therein on opposite sides of said upper opening,with said upper sheet having two oppositely disposed upper slits formedtherein that extend between said upper opening and said two upper ports,with said upper opening, said two upper ports and said two upper slitscooperatively defining two oppositely disposed upper flaps in said uppersheet that deform upwardly to wipe mud from said drill pipe that mayhave entered said space when said drill pipe is moved upwardly relativeto said device, which mud scraped from said drill pipe by said two upperflaps is contained within said space and subsequently drained therefromby gravity through said two lower ports into said well bore.

7. The device as defined in claim 6 wherein said pairs of upper andlower flaps are angularly disposed relative to one another.

8. The device as defined in claim 6 wherein said pairs of upper andlower flaps are normally disposed relative to one another.

9. The device as defined in claim 6 wherein the depth of said space issufficiently great that said pairs of lower and upper flaps remain outof contact when deformed upwardly to wipe said mud from said drill pipe.

lfll. The device as defined in claim 6 wherein said drill string has abit of greater external diameter than the ex temal diameter of saiddrill pipe mounted on the lower end thereof, and said pairs of upper andlower flaps are of sufficient area and formed from rubber of such shorehardness that they may deform upwardly to permit said bit to passupwardly therethrough without damage to

1. In combination with an oil well drilling rig having a rotary tablethat includes a split bushing through which drill pipe that supports abit may be moved upwardly from a bore hole containing drilling mud, adevice for subjecting said drill pipe to a dual wiping action to removesaid mud therefrom as said drill pipe is moved upwardly relative to saidrotary table when said device is situated below said bushing, saiddevice including: a. a stiffener ring of substantially greater diameterthan the external diameter of said drill pipe; and b. a circular,generally flat, resilient body that includes a ring-shaped peripheralportion which envelopes said stiffener ring, with said body inwardlyfrom said peripheral portion developing into upper and lower sheets thatdefine a space of substantial depth therebetween, said upper and lowersheets having coaxially aligned upper and lower circular openings formedtherein of slightly lesser diameter than the external diameter of saiddrill pipe, and with those portions of said upper and lower sheetsdefining said upper and lower openings being in pressure wiping contactwith the exterior surface of said drill pipe, said lower sheets havingtwo oppositely disposed ports formed therein on opposite sides of saidlower opening, which lower sheet has two oppositely disposed lower slitsformed therein that extend between said lower opening and said two lowerports and said two lower slits cooperatively defining two oppositelydisposed lower flaps in said lower sheet that deform upwardly to wipemud from said drill pipe as the latter is moved upwardly relative tosaid device, and with any of said mud on said drill pipe that passessaid lower flaps entering said space and draining therefrom by gravitythrough said lower ports into said well bore.
 2. The device as definedin claim 1 wherein said stiffener ring is formed from rubber having afirst shore hardness and said body is formed from rubber having a secondshore hardness substantially less than said first shore hardness.
 3. Thedevice as defined in claim 2 wherein there is a differential of at least20 between the shore hardness of said body and said stiffener ring. 4.The device as defined in claim 2 wherein said first shore hardness liesin a range of between 80 and
 95. 5. The device as defined in claim 4wherein said second shore hardness is substantially
 60. 6. The device asdefined in claim 1 in which said upper sheet has two upper ports definedtherein on opposite sides of said Upper opening, with said upper sheethaving two oppositely disposed upper slits formed therein that extendbetween said upper opening and said two upper ports, with said upperopening, said two upper ports and said two upper slits cooperativelydefining two oppositely disposed upper flaps in said upper sheet thatdeform upwardly to wipe mud from said drill pipe that may have enteredsaid space when said drill pipe is moved upwardly relative to saiddevice, which mud scraped from said drill pipe by said two upper flapsis contained within said space and subsequently drained therefrom bygravity through said two lower ports into said well bore.
 7. The deviceas defined in claim 6 wherein said pairs of upper and lower flaps areangularly disposed relative to one another.
 8. The device as defined inclaim 6 wherein said pairs of upper and lower flaps are normallydisposed relative to one another.
 9. The device as defined in claim 6wherein the depth of said space is sufficiently great that said pairs oflower and upper flaps remain out of contact when deformed upwardly towipe said mud from said drill pipe.
 10. The device as defined in claim 6wherein said drill string has a bit of greater external diameter thanthe external diameter of said drill pipe mounted on the lower endthereof, and said pairs of upper and lower flaps are of sufficient areaand formed from rubber of such shore hardness that they may deformupwardly to permit said bit to pass upwardly therethrough without damageto said device.